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Synthesis of an isotopically labeled naphthalene derivative that supports a long-lived nuclear singlet state.

ABSTRACT: The synthesis of an octa-alkoxy substituted isotopically labeled naphthalene derivative, shown to have excellent properties in singlet NMR experiments, is described. This highly substituted naphthalene system, which incorporates an adjacent (13)C spin pair, is readily accessed from a commercially available (13)C2-labeled building block via sequential thermal alkynyl- and arylcyclobutenone rearrangements. The synthetic route incorporates a simple desymmetrization approach leading to a small difference in the chemical shifts of the (13)C spin pair, a design constraint crucial for accessing nuclear singlet order.

SUBMITTER: Hill-Cousins JT

PROVIDER: S-EPMC4516318 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Synthesis of an isotopically labeled naphthalene derivative that supports a long-lived nuclear singlet state.

Hill-Cousins Joseph T JT Pop Ionut-Alexandru IA Pileio Giuseppe G Stevanato Gabriele G Håkansson Pär P Roy Soumya S SS Levitt Malcolm H MH Brown Lynda J LJ Brown Richard C D RC

Organic letters 20150421 9

The synthesis of an octa-alkoxy substituted isotopically labeled naphthalene derivative, shown to have excellent properties in singlet NMR experiments, is described. This highly substituted naphthalene system, which incorporates an adjacent (13)C spin pair, is readily accessed from a commercially available (13)C2-labeled building block via sequential thermal alkynyl- and arylcyclobutenone rearrangements. The synthetic route incorporates a simple desymmetrization approach leading to a small diffe ...[more]

PMID: 25898076

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